The novel cytokine IL-31 and its receptor have been shown to play a central role in bridging the immune system with neurons, epithelial surfaces and connective tissues. Although increasing evidence has demonstrated their role in inflammation, their involvement in the expansion of distinct leukocyte subsets is not fully understood. Detailed analyses of Il31-transgenic (Eµ-Lck) mice indicated that next to the induction of pruritus and skin lesions, mice also presented enlarged lymph nodes with increased B cell frequency. Therefore, we aimed at characterizing the role of IL-31 signaling in B cell biology. Using flow cytometry, the frequency of total B cells and specific B cell subsets was assessed in peripheral lymph nodes and bone marrow of Il31-transgenic (Eµ-Lck) mice and wild-type controls. Moreover, IL-31RA expression was analyzed on human B cell subsets from peripheral blood of healthy and atopic dermatitis donors. We observed a significantly increased frequency of CD19+ B cells in bone marrow and peripheral lymph nodes in Il31-transgenic mice. Detailed analyses of B cell subsets indicated that Il31-transgenic mice showed a higher frequency of plasmablasts in peripheral lymph nodes. In human, memory B cells represented the major population expressing IL-31RA within the B cell compartment. Furthermore, atopic dermatitis patients with elevated IgE levels (>1000 kU/l) showed a higher IL-31RA expression on memory B cells compared to healthy donors. This is of particular interest since DOCK8 acts as a negative regulator of IL-31. DOCK8 deficiency-related hyper-IgE syndrome presents with elevated serum IgE levels and severe atopic dermatitis with increased IL-31 expression. Taken together, these findings point to a novel role of IL-31 in B cell biology and an atopic IgE-producing phenotype.

ESDR027 - Memory B cells of atopic individuals preferentially express IL-31RA: a putative role of IL-31 in B cell biology

The scientific meeting of the European Society for Dermatological Research (ESDR) is held yearly, usually in September. With an international attendance of more than 1000 skin scientists from around the globe, the four-day event includes short oral presentations from peer-reviewed abstracts, keynote lectures from international experts, sponsored symposia, satellite programs, educational events as well as an important focus on posters, networking and building collaborations amongst scientists. For more information about this year’s meeting visit our website.